Large transformers on the order of 150 kVA or more are used in a wide variety of industrial and commercial applications. Regardless of the application, users of these transformers demand high efficiencies as even small improvements (i.e., less than one percent) in efficiency translate into thousands of dollars in energy savings.
In addition to the efficiency issues, large transformers generate a substantial amount of heat that can cause the premature failure of supporting electrical components (e.g., circuit breakers) if they are in proximity to the transformers. Accordingly, such supporting electrical components are typically separated from the transformers. In terms of large transformer systems, such separation is usually accomplished using multiple cabinets/housings with the transformer(s) located in one cabinet and the supporting electrical components located in another cabinet. However, the use of multiple cabinets/housings adds to fabrication, handling, and maintenance costs.
Many transformer systems are difficult or nearly impossible to repair on site thereby subjecting owners to high maintenance costs. Further, many transformer applications require the transformers to reside outside in the elements. For example, marinas use transformers to step down line voltage for supply to a number of power pedestals distributed about a marina. Thus, transformer cabinet design can be critical to the protection of the housed electrical components. Still further, transformer cabinet design must be economical in terms of cost, size, weight, etc., in order to make the overall transformer system affordable and manageable in terms of transportation, handling and site placement.